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        <h2>
          <span class="refentrytitle">GEN04</span>
        </h2>
        <p>GEN04 — 
      Generates a normalizing function.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp213550160"></a>
        <h2>Description</h2>
        <p>
      This subroutine generates a normalizing function by examining the contents of an existing table.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp213594208"></a>
        <h2>Syntax</h2>
        <pre class="synopsis"><span class="command"><strong>f</strong></span>  #  time  size  4  source#  sourcemode</pre>
      </div>
      <div class="refsect1">
        <a id="idp213596208"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>size</em></span> -- number of points in the table. Should be power-of-2 plus 1. Must not exceed (except by 1) the size of the source table being examined; limited to just half that size if the sourcemode is of type offset (see below).
    </p>
        <p>
      <span class="emphasis"><em>source #</em></span> -- table number of stored function to be examined.
    </p>
        <p>
      <span class="emphasis"><em>sourcemode</em></span> -- a coded value, specifying how the source table is to be scanned to obtain the normalizing function. Zero indicates that the source is to be scanned from left to right. Non-zero indicates that the source has a bipolar structure; scanning will begin at the mid-point and progress outwards, looking at pairs of points equidistant from the center.
    </p>
        <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;">
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              </td>
              <th align="left">Note</th>
            </tr>
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              <td align="left" valign="top">
                <p>
        </p>
                <div class="itemizedlist">
                  <ul class="itemizedlist" style="list-style-type: disc; ">
                    <li class="listitem">
                      <p>
              The normalizing function derives from the progressive absolute maxima of the source table being scanned. The new table is created left-to-right, with stored values equal to 1/(absolute maximum so far scanned). Stored values will thus begin with 1/(first value scanned), then get progressively smaller as new maxima are encountered. For a source table which is normalized (values &lt;= 1), the derived values will range from 1/(first value scanned) down to 1. If the first value scanned is zero, that inverse will be set to 1.
            </p>
                    </li>
                    <li class="listitem">
                      <p>
              The normalizing function from <span class="emphasis"><em>GEN04</em></span> is not itself normalized.
            </p>
                    </li>
                    <li class="listitem">
                      <p>
              <span class="emphasis"><em>GEN04</em></span> is useful for scaling a table-derived signal so that it has a consistent peak amplitude. A particular application occurs in waveshaping when the carrier (or indexing) signal is less than full amplitude.
            </p>
                    </li>
                  </ul>
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                <p>
      </p>
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      <div class="refsect1">
        <a id="idp213605872"></a>
        <h2>Examples</h2>
        <p>
      Here is a simple example of the GEN04 routine. It uses the files <a class="ulink" href="examples/gen04.csd" target="_top"><em class="citetitle">gen04.csd</em></a>.
      </p>
        <div class="example">
          <a id="idp213607744"></a>
          <p class="title">
            <strong>Example 1094. An example of the GEN04 routine.</strong>
          </p>
          <div class="example-contents">
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac  <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o gen04.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100 
<span class="ohdr">ksmps</span> <span class="op">=</span> 32 
<span class="ohdr">nchnls</span> <span class="op">=</span> 2 
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1 

gisine   <span class="ohdr">ftgen</span> 0, 0, 16384, 10, 1						<span class="comment">;sine wave</span>

<span class="oblock">instr</span>   1

ihertz <span class="op">=</span> <span class="opc">cpspch</span>(p4)
ipkamp <span class="op">=</span> p5
iwsfn  <span class="op">=</span> p6									<span class="comment">;waveshaping function	</span>
inmfn  <span class="op">=</span> p7									<span class="comment">;normalization function 								</span>
agate   <span class="opc">linen</span>   1, .01, p3, .1            					<span class="comment">;overall amp envelope</span>
kctrl   <span class="opc">linen</span>  	.9, 2, p3, 2							<span class="comment">;waveshaping index control</span>
aindex  <span class="opc">poscil</span>  kctrl<span class="op">/</span>2, ihertz, gisine						<span class="comment">;sine wave to be distorted</span>
asignal <span class="opc">tablei</span>  .5<span class="op">+</span>aindex, iwsfn, 1						<span class="comment">;waveshaping</span>
knormal <span class="opc">tablei</span>  1<span class="op">/</span>kctrl, inmfn , 1						<span class="comment">;amplitude normalization</span>
        <span class="opc">outs</span>    asignal<span class="op">*</span>knormal<span class="op">*</span>ipkamp<span class="op">*</span>agate, asignal<span class="op">*</span>knormal<span class="op">*</span>ipkamp<span class="op">*</span>agate
           
<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="stamnt">f</span>1 0 64 21 6	<span class="comment">;Gaussian (random) distribution</span>
<span class="stamnt">f</span>2 0 33 4 1 1	<span class="comment">;normalizing function with midpoint bipolar offset</span>

<span class="stamnt">s</span>
<span class="comment">;	st	dur	pch	amp   wsfn inmfn</span>
<span class="stamnt">i</span>1      0       4      6.00    .7      1     2
<span class="stamnt">i</span>1      4       .      7.00    .
<span class="stamnt">i</span>1      8       .      8.00    .
<span class="comment">;-------------------------------------------------------------------------------------</span>
<span class="stamnt">f</span>3 0 1025 13 1 1 0 5 0 5 0 10	<span class="comment">;Chebyshev algorithm</span>
<span class="stamnt">f</span>4 0 513 4 3 1			<span class="comment">;normalizing function with midpoint bipolar offset</span>
<span class="stamnt">s</span>
<span class="comment">;	st	dur	pch	amp   wsfn inmfn</span>
<span class="stamnt">i</span>1      0       4      6.00    .9      3     4
<span class="stamnt">i</span>1      4       .      7.00    .
<span class="stamnt">i</span>1      8       .      8.00    .
<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />

        <span class="phrase">These are the diagrams of the waveforms of the GEN04 routines, as used in the example:</span>

      </p>
        <div class="mediaobject">
          <img src="images/gen04_1.png" alt="f1 0 64 21 6 - Gaussian (random) distribution" />
          <div class="caption">
            <p>f1 0 64 21 6 - Gaussian (random) distribution</p>
          </div>
        </div>
        <p>

      </p>
        <div class="mediaobject">
          <img src="images/gen04_2.png" alt="f2 0 33 4 1 1 - AND its normalizing function with midpoint bipolar offset" />
          <div class="caption">
            <p>f2 0 33 4 1 1 - AND its normalizing function with midpoint bipolar offset</p>
          </div>
        </div>
        <p>

      </p>
        <div class="mediaobject">
          <img src="images/gen04_3.png" alt="f3 0 1025 13 1 1 0 5 0 5 0 10 - Chebyshev algorithm" />
          <div class="caption">
            <p>f3 0 1025 13 1 1 0 5 0 5 0 10 - Chebyshev algorithm</p>
          </div>
        </div>
        <p>

      </p>
        <div class="mediaobject">
          <img src="images/gen04_4.png" alt="f4 0 513 4 3 1 - AND its normalizing function with midpoint bipolar offset" />
          <div class="caption">
            <p>f4 0 513 4 3 1 - AND its normalizing function with midpoint bipolar offset</p>
          </div>
        </div>
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